A light emitting diode (LED) is one of semiconductor devices that emit light when a current is applied thereto. The LED is capable of emitting light with high efficiency at a low voltage to have an effect of significant energy saving. Recently, a luminance problem of the LED has been significantly improved, and thus the LED is being applied to various devices such as backlight units of liquid crystal display devices, electronic sign boards, indicators, home appliances, and the like.
The light emitting diode may have a structure in which a first electrode and a second electrode are disposed on one side of a light emitting structure including a first semiconductor layer, an active layer, and a second semiconductor layer. Further, the first electrode and the second electrode may be electrically connected to an external circuit through lead frames.
However, the lead frames disposed below the LED are each made of a metal material such as gold (Au) and there is a problem in that the metal material absorbs light to degrade a light flux. In order to solve the above problem, when the lead frame is coated with silver (Ag) or the like, there is problem in that a surface of the lead frame is discolored and thus reliability is degraded.